I have the rear one Replaced main seal on a 1998 Ford F150 4.2 V6 at 165,000 miles with this Victor Reinz seal on my first clutch change. I found a small oil leak on the original Ford rear seal. So it was good to replace that oil seal. I have found that the best way to remove the old gasket is to drill an 11/64 pilot hole right in the center of the old gasket's front wall and then carefully drive a 2" fine-pitch drywall screw through the old gasket to screw. and into the back of the engine, displacing the old oil seal right out of the channel. To fit a new oil seal, first lubricate it with a thin coating of clean engine oil, then gently press it into place with your fingers! Then use a 3/8 inch extension and a hammer to lightly tap the gasket to set it in place. To finally assemble the new seal, place the old rear seal on top of the new seal and use a hammer. Gently tap the old gasket against the new gasket and place it in its final position. Voila - no more oil leaking through the rear main seal. I have also used Victor Reinz on other gaskets such as upper/lower intake manifold and head gaskets and have been impressed with their fit and performance. Highly recommended.